Spark-plug.



E. L. SUESS.

SPARK FLUG.

APPLICATION FILED MAR. 8. 1916.

1,220,472. Patented Mar. 27, 1917.

EDMUND L. SUESS, 01E PITTSBURGH, PENNSYLVANIA.

SPARK-PLUG.

Specification of Letters Patent.

Patented Mar. 2'?, 1917,

Application filed. March 8, 1916. Serial No. 82,831.

he invention has for its object to provide an eiicient plug of the kind stated, having a few, relative simple parts, which can readily be assembled, and which may be easily removed and replaced when they become broken or disordered.v

i The invention also has for its object to provide a double-gap spark plug which is compact and conforms to the present standard type of spark plugs.

4Other objects and advantages of the in,

vention will be pointed out in the detailed description appearing hereinafter, and in order that the same may be better understood reference is had to the accompanying drawing, in which-# Figure'v 1 is an elevation of the plug 2 is a central vertical section thereof, and Fig. 3 is a cross section on the line 3 3 of Fig. 1.

Referring specifically to the drawing, 5 denotes the usual porcelain body of the plug, the same being fitted at one end into a metallic base shell 6 of standard shape, and having a reduced threaded end to screw into the engine cylinder. v'I`heupper end of the shell is formed with a stuffing box which receives a gland 7. That portion of the plug 5 which is in the stufiing'box has a shoulder 8 which seats againsta washer 9 in the bottom of the stuiiing box, and between the shoulder and the inner end of the gland is interposed a washer 10. The shell 6 has two sparking terminals 11 at the cylinder end, whereby wear `is distributed between two points. The gland 7 securely holds the plug 5' in the shell 6, and leakage of gas is effectually prevented by the washers 9 and 10.

Extending through the upper part of the plug 5 is a terminal rod 12, and fitting in a' recess at the top of the plug is an adjusting nut 14 for movin the rod in the direction of'its lengthfThis nut isv cemented into, or

otherwise fixed' in the recess, and any adiustment of the rod is made by turning the latter, it being threaded through the nut. Over the nut 14, and itting against a shoulder on the plug 5 is a. csi-p15 through which the upper end of the rod 12 passes, and above said cap, the -rod carries a jam nut 16, which latter, when it is screwed down against the cap, locks the rod in adjusted position.

The cap 15 has a. depending marginal ilange 17 provided at the bottom, at diametrically opposite points, with inturned segments 18 which seat in grooves 19 in the sides of the plug 5. Between `the grooves 19, the Sides of the plug are iattened, as indicated at 20. vThe segments 18 slide over the flattened portions of the plug, and they are seated in the. grooves 19 by giving the cap a quarter turn, and after the nut 16 is screwed down, the cap is prevented from`V turning further on the plug, so that the rod 12 is now securely held even if the nut 14' should get loose.

ln the lower part of the plug 5., in aXial alinement with the rod 12, is mounted the .secOnd terminal rod 21.' A shoulder or abutment 22 on the upper end of the rod 21 seats in a recess in the plug, and this `shoulder is made small enough to pass through a longitudinal hole 23 in the upper end of the I plug, in which hole the rod 12 seats, and

thus, 'the rod 21 may be pushed through the hole 23 from the top of the plug when the parts are assembled. Around the rod 21, at the bottoni` or cylinder end of the plug 5,

is placed a brass washer 25 which packs the former over the opening 26 in the plug in which-therod'21 seats, and prevents escape of any compression. A nut 27 screwed on the rod 21 holds the brass washer 25 to the packing washer. The parts also serve as an abutment to prevent upward movement of the rod 12 in the plu ,is mounted an asbestos washer 24 over which 1 ln the upper end othe plug 5 is a transverse sight opening 28 closed at its ends by some suitable transparent material 29. This openingis located to render visible the adjacent ends of the rods 12 and 21 in order rod 21 is pushed down through the openings 23 and 26 until the shoulder 22'seats in the recess in the plug 5. The washers 24 and 25 are then applied, and the nut 27 is screwed on tight. The upper terminal rod 12 is next pushed through the opening 23, and the distance between the spark points of the two rods is adjusted by turning the upper rod in the nut 14. After the nut 14 is' secured in the recess 13, the cap 15 is put in place and the jam nut 16 is screwed down thereon.

The plug 5 is then placed in the shell 6 and secured therein by the gland 7. The transparent closures 29 of the opening 28 are cemented or secured in any other suitable manner to prevent any external explosions and to make the device fireproof.

In use, one yof the wires of theignition circuit will be connected to the outer end of the upper terminal rod 12. The current passing through this rod jumps the gap between the lower end thereof and the adjacent upper end of the lower terminal rod 21. The spark thus-produced at the gap may be readily observed at the opening 28, thus indicating whether sparking is taking place at the inner terminals 11. The device therefore has the function of a spark plug and a tester, and it will instantly locate trouble in the ignition system.

The form and construction of the device conforms to that of the present standard spark plugs, and the object-sought is attained without the use of auxiliary wires, connections, etc. The structure is simple and compact, and any broken or disordered parts can be readily removed and replaced. The manner of securing the two terminal rods elfectually prevents relative longitudinal movement thereof to disturb 'the adjustment, the upper rod being securely held against downward movement and the lower rod against upwardv movement.

.I claim: l

1. A spark plug having a bodyof insulating material provided with a transverse lsight opening axially alined up er and lower terminal rods mounted in said body,

the adjacent ends of the rods extendin into the. opening andbeing spaced to pro uce a spark gap therein, a mit fixed on the outer end of the body through which. nut the upper rod is threaded for longitudinal adjust- `ment, said end of the body having a recess' in which` the nut seats, a cap mounted on -the outer end of the body over the nut, said.

cap -having a depending marginal flange provided with diametrically opposite inturned ends, and the side of the body having grooves in which said inturned ends seat between which grooves the side of the body is flattened, a jam nut on the upper rod screwed against the cap, and means yfor locking the lower rod against movement longi-l tudinally in" either direction.

2. A spark plug having an integral body of insulating material provided with a abutment being not greater than the diam! eter of said opening, and an abutment on the lower rod engaging the inner end of .the body.

V3. A spark plug having an integral body of insulating material provided withv a transverse sight-opening; axially alined up- -per and `lower terminal rods mounted in lsaid body,l the adjacent ends of the rods extending into theopening and being spaced to produce a spark gap therein, and an abutment on the `lower rod, the body having a recess in which the abutment seats andl a longitudinal opening above the" said recess inwhich the upper rod seats, the width of `the abutment beingwnot greater than the diameter of said opening.

In testimony whereof I aiix my signature in the presence of two witnesses.

EDMUND L. SUESS. Witnesses:

vWILLIAM A. GOLDEN, 'JosEPH F. Wars. 

